Ethanol → (R)-8-Methyl-5-(4-nitrophenyl)-7-(5-methyl-1,3,4-oxadiazol-2-yl)-8,9-dihydro-7H-1,3-dioxolo[4,5-h][2,3]benzodiazepine

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Reaction Steps

A stirred mixture of 2.2 g (5.15 mmol) of (R)—N′-(8-methyl-5-(4-nitrophenyl)-8,9-dihydro-7H-1,3-dioxolo[4,5-h][2,3]benzodiazepin-7-carbothioyl)-acetic hydrazide (an intermediate of method B of Example 28), 44 ml of ethanol and 1.72 g (5.39 mmol) of mercury (II) acetate was refluxed for 2 h. The residue obtained on concentration was dissolved in dichloromethane and filtered through a neutral aluminum oxide column. After washing the column the filtrate was concentrated and the residue was purified by column chromatography using silica gel (MN Kieselgel 60) as adsorbent and a mixture of n-hexane-ethyl acetate (1:2.5) as eluent to yield 1.07 g (51%) of the title compound. Mp.: 202-204° C. after recrystallization from ethanol. [α]: −249° (c=0.22; CHCl3).

Provenance & Evidence